408 
Glycyrrhizin  in  Licorice  Root. 
5  Am.  Jour.  Pharm. 
X      June,  1921. 
ammoniated  glycyrrhizin  is  evaporated  to  dryness  on  the  water  bath, 
and  weighed.   A  weight  of  at  least  0.2  g.  is  required." 
This  Pharmacopoeia  method  does  not  state  in  how  much  water 
the  licorice  is  to  be  dissolved.  I  always  used  30  cc.  and  washed  the 
insoluble  residue  until  I  had  100  cc.  nitrate.  The  filtration  took  a 
long  time.  For  the  precipitation,  30  drops  of  official  hydrochloric 
acid  were  used  (Sp.  Gr.  1.171,  22 0  Be.),  which  method  I  adopted. 
The  nitration  of  the  precipitated  acid  takes  a  very  long  time  if  a 
smooth  filter  is  used.  Therefore  in  the  following  experiments  I 
always  used  a  fluted  filter.  Three  8  cc.  portions  of  water  are  not 
sufficient  to  wash  the  glycyrrhizin  precipitate  until  colorless.  There 
is,  therefore,  the  possibility,  that  water-soluble  materials  which 
should  be  washed  out,  are  later  weighed  as  ammoniated  glycyr- 
rhizin. It  is  quite  incomprehensible  why  the  French  Pharmacopoeia 
specifies  a  solution  of  the  glycyrrhizin  salt  in  100  cc,  and  precipitates 
the  acid  from  this  large  volume  of  water.  Twenty  cc.  of  liquid  would 
be  quite  sufficient.  The  use  of  such  a  large  excess  of  water  results 
in  very  appreciable  losses.  The  precipitation  takes  place  with  hydro- 
chloric acid,  but  the  amount  of  acid  prescribed  is  much  too  small,  so 
that  not  all  of  the  glycyrrhizin  is  precipitated,  an  observation  which 
Capin  himself  made.  If  after  adding  the  hydrochloric  acid  accord- 
ing to  directions,  the  mixture  is  allowed  to  stand  24  hours  and  the 
glycyrrhizin  filtered  off,  the  filtrate  shows  a  further  precipitate  on 
standing  when  additional  hydrochloric  or  sulphuric  acid  is  added. 
[Translator's  Note. — Other  objections  to  this  method  are  men- 
tioned, including  the  fact  that  alcohol  is  not  used.  (P.  A.  H.)] 
The  values  which  I  have  found  for  the  losses  involved,  prove 
sufficiently  that  the  method  of  the  new  French  Pharmacopoeia  is  en- 
tirely useless.  It  is  really  quite  remarkable  that  even  in  1908  sucri  a 
poor  method  could  be  adopted  when  a  whole  series  of  publications 
were  available  which  would  have  given  practical  results. 
5.  Diehl  (1883). 
"Ten  g.  licorice  are  digested,  until  disintegrated,  with  10  cc.  dis- 
tilled water  in  a  flask.  After  cooling,  200  cc.  of  alcohol  are  added, 
and  allowed  to  stand  several  hours  with  frequent  shaking.  The 
liquid  is  then  filtered  through  a  double  filter  and  the  residue  washed 
with  a  mixture  of  alcohol  and  water  (2:1)  until  the  filtrate  is  color- 
less.   The  alcoholic  filtrate  is  evaporated  to  a  syrup,  dissolved  in 
